happner/docs/starting.md

distributed application engine with evented storage and mesh services

[◀](data.md) data api | system components [▶](system.md)

## Starting and Stopping a Mesh Node.

MeshNode startup has been divided into two steps.

##### Initialize

* Starts all local internal infrastructure
* Begins listeing on the network.
* Generates local module and componentInstances per the config
* Begins connection attempts to remote MeshNodes (endpoints)
* Assembles the exchange and event api layers
* Ammends the exchange and event api with each established connection to remote MeshNodes
* Reports initialized! (runlevel 20)

##### Start

* Calls the start method on any components that specified one. This allows components an initialization step that occurs after all mesh connections have been made.
* Reports started! (runlevel 40)

These two steps can be done separately (by hand).

```javascript
var Happner = require('happner');

var config = {};
var mesh = new Happner();

mesh.initialize(config, function(err) {
  if (err) ... process.exit(1);

  /* MeshNode is up */

  /* Maybe do some things to mesh before "start" */

  mesh.start(function(err) {
    if (err) ... process.exit(2);

    /* MeshNode is up - AND running */

  });
});

```

Alternatively, there may be no reason to get inbetween the runlevels, so one call to the 'factory' will do.

```javascript
var Happner = require('happner');
var config = {};

Happner.create(config, function(err, mesh) {
  /* _ */
});
```

The `create()` also returns a promise

```javascript
Happner.create(config).then(...
```

##### Stop

Given an already started `mesh` instance. (show with defaults)

```javascript
mesh.stop({
  kill: false,    // kill the process once stopped
  wait: 10000,    // wait for callbacks before kill
  exitCode: 1,    // when kill, exit with this integer
  reconnect: true // inform attached clients/endpoints to reconnect
}, function(data) {
  console.log('stopped');
});

```